1. Field of the Invention
This invention relates to a vacuum box that collects debris created by a tractor and discharges the debris through a chute.
2. Description of the Prior Art
Vacuum boxes are used to collect water, pulverized asphalt, paint, rubber, thermoplastic, tape, and curing compounds and other debris created when high pressure water is discharged by a nozzle bar mounted on a tractor to remove pavement markings or coatings from roads, airport runways, taxiways, parking lots, and the like. A vacuum is maintained in the box to pull such debris from the water-blasted surface into the hollow interior of the vacuum box.
Problems arise when the typical vacuum box is full or substantially full. The weight of a full vacuum box can be substantial so emptying it can be difficult. The conventional emptying method uses an integral tilting cylinder to lift and tilt the vacuum box to discharge its contents. Such elevation of the center of gravity creates a stability hazard and can result in a rollover of the vacuum box.
Thus there is a need for a vacuum box that can be emptied without being inverted, tilted, or pivoted, thereby eliminating stability hazards.
However, in view of the prior art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the art that a better vacuum box was needed nor was it obvious how a conventional vacuum box could be improved.